As time goes by, the concept of a "smart city" encompasses an increasing number of aspects. Essentially, when we think of a modern city, we would like it to offer a vibrant and safe living environment for its community of residents: healthy indoor living spaces, green outdoor spaces for leisure and sports, flowing traffic, efficient distribution of goods, various forms of safe transportation for people, public lighting and surveillance systems, emergency management, information and communication services, etc. A smart city offers much more: it represents a space that favors the development of people and their potential, in a sustainable and resilient manner, by means of the intelligent integration of ICT tools and technologies. The following reprint collects research and innovative approaches to smart city issues. The contributions cover a wide range of topics, from car and bike-sharing models to ways of improving quality of life through digitalization. Readers will get an insight into effective solutions offered by researchers and practitioners working in artificial intelligence, the Internet of Things, data analytics, etc. The synergy of these technologies is illustrated herein, providing a new, challenging view on the smart cities of today and of the future.